1. Field of the Invention:
This invention relates to incendiary compositions for producing incendiary components for munitions and other incendiary devices. More specifically, this invention relates to incendiary compositions produced from zirconium or hafnium sponge metal compacted in a binder. The binder is of an organic nature and can be any fluorocarbon polymeric material.
2. Description of the Prior Art:
Incendiary compositions are used for a wide variety of purposes, from propellant fuels to welding to munitions. Many munitions such as High Explosive Incendiary projectiles fired from guns, bombs guided or free fall, bomblets, grenades, kinetic energy projectiles and shaped charge warheads are designed to contain an incendiary material to ignite the combustible materials within the influence area of the munition. Many of the incendiary compositions incorporated into the design of these weapons contain low density metal powders such as aluminum or magnesium combined with a variety of oxidizer materials usually referred to as pyrotechnic compositions. Another incendiary material commonly used in many munitions is white phosphorus which has poor performance characteristics, is hazardous, difficult to load, and limited in its application to many munition designs.
Other compositions containing zirconium and titanium metal in organic binders have been known to be used in incendiary compositions. Examples of these are illustrated in several patents. For example, Patent 3565706 discloses an incendiary composition containing a fluorocarbon such as teflon and a metal powder such as zirconium, uranium, tantalum and vanadium. The composition disclosed in this patent is primarily for a fuel although it does state that it can be used for ordnance material. In this patent the fluorocarbon is present in a large amount and acts mainly as a binder. The metals are used in the form of fine powders of a size of from 1 to 300 microns. This composition has certain drawbacks when used as an incendiary composition in a fire bomb type ordnance material. Due to the fine size of the metal particles, the projection of these particles on impact is of a limited area because of the light weight of the particles.
Some other patents disclosing an incendiary composition containing a fluorocarbon as a binder and zirconium metal are Patents 3734788, 3876477 and 3753811. All of these patents disclose compositions containing large amounts of fluorocarbon and zirconium metal along with other compounds. The first two refer to propellants and are drawn to slow burning fuels while the latter is an igniter device for propellants, fuels and explosives. All of these compositions have the drawback associated with the use of metal particles wherein the size of said particles is of a very fine nature to give it its pyrotechnic quality.
Finally, there is the Griffin Patent 3927993 which discloses an incendiary composition for a fire starter which can be used in ordnance material as stated in the specification thereof. This reference discloses the use of zirconium, titanium and hafnium sponge metal compacted with a binder. It suggests various binders including some resinous compositions and a wide range of mesh size for the metallic sponge.
None of the above patents, however, disclose the use of zirconium or hafnium sponge in a fluorocarbon binder which, although encompassed under the Griffin Patent, does have certain unknown qualities particular to this specific combination.